WO1989003266A1

WO1989003266A1 - Machine-tool, clamping accessory and tool head

Info

Publication number: WO1989003266A1
Application number: PCT/EP1988/000916
Authority: WO
Inventors: Franz Wachter
Original assignee: KROLL, Klaus-Dieter
Priority date: 1987-10-13
Filing date: 1988-10-12
Publication date: 1989-04-20
Also published as: EP0382758A1; KR890701258A; JPH03504831A

Abstract

A machine tool, in particular a lathe, with a turret axis (15) parallel to a machining axis, comprises a plurality of fixing devices (17, 19) arranged on the turret (113) and in which are inserted, instead of tool heads, clamping accessories (18) fixed by means of rapid closing fixing devices (17, 19). The clamping accessories (18) ensure precise adjustement on a peripheral circle (12) of the turret (113) and preferably have at least two facing holding devices (18.6) for a part of a tool head which are also connected to rapid closing devices (25 27).

Description

MACHINE TOOL AND CLAMPING ADDITION AND TOOL HEAD FOR IT

The invention relates to a machine tool, and in particular to a lathe, according to the preamble of claim 1, and to a clamping attachment and a tool head therefor.

Within the meaning of the invention, “fastening devices” as “connections”, “clamping attachments” as “tool edge holders” and “tool heads” as “tool holders” are also understood.

There are numerous lathes on the market that have a quick-release fastener for the quick change of tools. For this purpose, numerous different designs have already been proposed, one of which has become particularly popular as the VDI clamping system. The term “lathe” is understood today to mean any processing machine in which the workpiece and / or tool is machined for machining. It is known per se to attach the tools to a turret so that a quick change can take place. However, a disadvantage of all these designs is that the number of tools to be connected is usually limited.

A multi-tool holder has become known from DE-AS 23 41 999, but only for a very limited area of application, namely for grooving circular grooves with the aid of two tools pointing essentially in the same direction, which are intended to come into effect one after the other on a workpiece .

US Pat. No. Re 29,612 describes a revolver, on the circumferential surface of which tool holders can be fastened by means of several screws (usually four). Neither rapid removal of the tool holder nor a number of tools beyond the number of fastening points for tool holders can be attached here. For many tools, a tool head is provided, which is either attached to the tool or releasably connected to it, and which is attached to the tool holder.

DE-OS 34 30 380 now describes an interchangeable tool head with several chucks for the detachable fastening of several tools. However, chucks are not suitable for quickly changing the tools because the correct position of the tool and its outstanding length must first be laboriously adjusted in the chuck, which is correspondingly labor-intensive. Especially for NC machines that have a numerical control for automatic processing, tools with specified masses and dimensions are mostly used, as well as the quick-release fasteners mentioned.

Nevertheless, in many cases, an "O" production run must first be carried out in order to enable the correct tool or machine setting for a special workpiece.

Finally, it is known from FR-A-2 486 848 to provide a turret head with receiving holes which are continuous from one end face to the other for fastening tools. However, it is only possible to attach a tool to one or the other of the end faces, but not to equip both end faces with tools at the same time, for example, to process two opposite end faces of a groove immediately one after the other without having to change over.

Another problem with machine tools is the mostly given, not too great accuracy. However, if you want to process pieces with greater dimensions, special special machines are usually required, the purchase of which is expensive and the workload is usually low. Alternatively, only complex computer programs that cannot be used for many NC machines could remedy such defects.

The invention is therefore the object. to improve a machine tool of the type mentioned at the outset in such a way that on the one hand the tool change can be carried out quickly, either a larger number of tools can be kept on standby without much changeover time and also the machining time is shortened and / or the machining accuracy - even with existing machine tools - without increasing investment costs.

To achieve this object, at least one of the features mentioned in the characterizing part of claim 1 is provided according to the invention, which are to be discussed below.

The feature a) makes it possible to adjust each clamping attachment assigned to a fastening device with respect to the fastening device and the turret axis such that its own fastening device, namely the other of the clamping attachment, lies precisely on a circle traversed by all tools when the turret head rotates . In the simplest case, the adjustment can be carried out with the help of intermediate layers, but the arrangement can also be made such that the fastening parts on the clamping attachment for fastening to the turret are equipped with adjustment eccentrics in order to be able to carry out an exact alignment.

Alternatively, the clamping additives can be designed according to the features of claim 10. The above advantages also apply to an embodiment according to feature b), it being essential that a drive transmission can also be carried out via the tensioning attachment.

Even if the feature c) is realized, the advantages in terms of greater accuracy can be realized, but also the provision of a larger number of tools that can be used without changeover time.

The above-mentioned features a) to c) therefore have in common that a clamping attachment can be fastened to the fastening devices of the turret head, which in turn carries fastening devices for a tool holder or a tool head and through which the positioning of the tool can be placed more precisely at a preselected location. This has a particularly advantageous effect when retrofitting existing machine tools, for example grinding or planing machines with a reciprocating movement, but mostly lathes, which can now be brought to greater accuracy and economy without high investment costs. Characteristic c) also increases the number of tools to be carried by a turret by multiplying its existing fastening devices by the clamping attachment, whereby rapid tool changes are also possible here thanks to the design with quick-release fasteners. This means that a clamping attachment can already be fully equipped while the machine is working and then only needs to be connected to the fastening device of the turret. It is absolutely not necessary for the tensioning attachment to have only the two quick-release fasteners; for example, it can itself be designed as a revolver, which then sits on a larger revolver. Machining that is carried out in succession with several tools can be done faster be carried out because a small (additional) revolver is naturally more manageable. If the control system is designed accordingly, two workpieces can even be worked at the same time, or at least in quick succession.

Machining in two opposite directions is also possible and speed. Accuracy is also increased by feature d) - while reducing the changeover time due to the elimination of lengthy adjustment and dimensioning. This feature allows the tool dimensions, which ultimately indicate the position of the tool relative to the workpiece, to be automatically communicated to the control system without the need for manual input.

A clamping attachment according to the invention is characterized by the features of claim 2, a tool head according to the invention by the features of claim 9.

By interposing an additional part, namely the clamping additive, in addition to the tool head, it would have been assumed that there would be more noise due to vibrations during the machining, and in this regard there were also some concerns before the practical use of the invention. It is surprising that, on the contrary, the invention has led to a reduction in working noise. In retrospect, it can only be assumed as an explanation that the individual connections via the fastening devices are rigid enough to connect the individual parts to form an integral overall part, but since each of the individual parts has a different natural frequency, the tendency to vibrate noise decreases.

Further details of the invention will become apparent from the hand the following description of exemplary embodiments schematically illustrated in the drawing. Show it:

1 shows a lathe according to the invention in perspective;

2 shows an end view of a tool turret with a clamping attachment attached to it according to a first embodiment;

Fig. 3 shows another embodiment of the clamping attachment in a view corresponding to the line III-III of Fig. 2, partially in elevation, for what

FIG. 4 shows a view corresponding to the arrows IV of the FIG. 2, but the embodiment according to FIG. 3 illustrates together with two associated tool heads in an exoloded representation;

FIG. 5 shows a detail from FIG. 2, which shows the quick-release fastener in an axonometric representation;

Fig. 6 is an axonometric view of a modified

Embodiment of the clamping attachment with a conical coupling surface for the tool head;

FIG. 7 shows a variant of the quick-release fastener according to FIG. 5;

Fig. 8 shows a section through an optical reading device for a tool code, and

FIGS. 9 and 10 each show a modified embodiment of a tensioning additive in a section similar to FIG. 3, but somewhat enlarged.

A lathe 1 (FIG. 1) has a chuck 2, in which a workpiece can be clamped, as well as tools 3, 4, which are used to machine such a workpiece. The workpiece is over that Chuck 2 can be rotated with the aid of a drive shaft 5, for example in order to be able to carry out a recess using tool 4. The drive shaft 5, which is only indicated by dash-dotted lines, carries at its other end a drive wheel 6 which receives its drive from a wheel 8 seated on a hollow shaft 7. The wheel 8 is connected to a drive motor 9 via a clutch 10, the shift lever 11 of which can be brought into three different positions, the hollow shaft 7 being coupled in the uppermost position shown, a shaft 7 passing through the shaft 7 in a central position and in which lowest switch position only the latter.

The tools 3, 4 can be brought into the respective working position with the aid of a revolver 13, which also carries further tools on its peripheral surface 14 and which can be brought into individual discrete positions with the aid of a shaft 15. It is moved by a numerical control, housed in a switch box 16, in such a way that the tools 3, 4, etc. automatically execute an entered machining program.

It can be seen that the revolver 13 not only carries tools 3, 4 pointing to the left (with reference to FIG. 1), but also tools 3 ', 4' pointing in the opposite direction. These tools 3 ', 4' are assigned a second chuck 2 'opposite the first, which can be driven via a shaft 5', a wheel 6 'and a wheel 8' seated on the shaft 7 '. Thus, in exceptional cases in which the tools 3, 3 'and 4, 4' lying opposite one another have to carry out the same movement, it is possible to machine two workpieces simultaneously, or else to clamp a workpiece in one of the chucks while. another workpiece is machined on the other chuck so that the Ge total processing time reduced. In the latter case, the two chucks 2, 2 'are successively coupled to the motor 9. As will be explained later with reference to FIG. 2, this mode of operation is by no means mandatory if the increased number of tools to be clamped is provided on an additional turret.

According to FIG. 2, a somewhat smaller revolver 113 is provided, which has insertion openings 17 arranged along a circular path 12 for fastening a clamping attachment 18. While the insertion holes 17 usually serve to fix a tool therein with the aid of clamping jaws 19, which are only indicated by dashed lines, according to the invention a substantial increase in the tools to be connected can be achieved by using the clamping attachment 18.

This clamping attachment 18 has an elongated prismatic body 18.1, of which a pin-like projection 18.2 which can be pushed into the insertion opening 17

(cf. FIGS. 3, 4) protrudes from a fastening surface 18.3 opposite the end face 20 of the turret 113. As can be seen from FIGS. 3 and 4, the contact surface 18.3 can be provided on a separate plate 18.4 connected to the body 18.1.

At its end facing away from the pin 18.2, the body 18.1 expediently carries an approximately T-shaped crossbar 18.5 extending towards it. In itself, this design is not absolutely necessary if the body 18.1 has the necessary thickness in order to be able to accommodate opposing insertion holes 18.6 for a tool head 21 or 21 '(see FIG. 4). The crossbeam 18.5, however, with its section spanning the peripheral surface 14 of the turret, also has favorable effects on the strength and stability of the connection It is thus possible to assign each fastening device 17, 19, which can have relatively large tolerances in conventional design, to a special clamping additive 18 and to adjust this, for example by intermediate layers, to the dimensional deviations of the respectively associated fastening device so that the existing tolerances are compensated for and thus every tool comes to lie exactly on a circle,

- The tool heads or tool tips are immediately after locking in the clamping attachment 18 in exact positions relative to the machining axis of the machine. whose center is formed by the turret axis 15. If necessary, the clamping attachment 18 can be equipped with special adjustment devices, for example by the pin 18.2 being attached to the prismatic body via an adjustment eccentric (not shown), which may be rotatable about an axis parallel to the pin longitudinal axis.

An optical reading device 22 is attached to the revolver 113 on its circumferential surface 14 in such a way that it lies opposite a tool holder attached to the crossbar 18.5. The structure of this reading device 22 is shown in FIG. 8 by way of example. In any case, it is oriented in such a way that a code shown in FIG. 4 on the tool head 21, in particular a bar code 23, can be read automatically. This code 23 indicates the position of the tool attached to the tool head 21; A corresponding signal is communicated by the reading device 22 to the control 16 via a line guided through the turret shaft 15 (FIG. 1) or via sliding contacts, which would otherwise have to have this information entered via its keypad 16.1 in order to be able to guide the tool correctly. In the case of a tool head 21 (FIG. 4) or 21 'which can be releasably attached to the tool, code 23 can, however, only indicate the position of the tool holder 24, which, depending on the size of the tool head 21 or 21' will be different, ie code 23 indirectly indicates a dimension of the tool attached to the tool head. If, on the other hand, the tool is firmly connected to the tool head, code 23 can also be used to specify the tool length and thus the location of its end of machining. A similar reading device 22 'can also be arranged on the tensioning attachment 18, as illustrated in FIG. 3.

In order to be able to fasten the tool heads 21 and 21 'quickly and securely in the insertion openings 18.6, they are provided with a snap lock. This is shown in detail in Fig. 5 and consists essentially of a wedge slide 25 which carries a clamping wedge 25.1 on one side. The clamping wedge 25.1 can be brought from the position shown in full lines in FIG. 2 into a position shown in broken lines, in which it engages in a neck groove 21.1 of the tool head 21 or 21 '(FIG. 4). The wedge slide 25 is expediently cylindrical, so that a corresponding bore 26 in the crossbar 18 is easy to produce. Within this bore 26, the wedge slide 25 may itself be displaceable by any means, for example also by a fluidic, such as hydraulic, clamping devices, but it is easiest to provide an actuating device with a screw 27 for this purpose. As can be seen from FIG. 2, the screw 27 passes through the wedge slide 25 and is screwed into a threaded bore 18.7 of the crossbeam 18 at the other end. A spring 28 is preferably provided for the backward movement of the wedge slide 25.

The transverse baffle 85 can optionally be connected to the prismatic body 18.1 via a pivot pin 18.8 and can thus be rotatably fastened to the body 18.1. In this way, the crossbar 18.5 forms a kind of additional revolver since a tool 3 'or 4' (cf. FIG. 1) easily get into the position of a tool 3 or 4 can. The number of insertion holes 18.6 is by no means limited to two, rather the cross bar 18.5 could have one insertion hole on each of its sides, possibly also two according to the proposal of DE-AS 23 41 999. It can be seen that in this way the holding capacity of the revolver 13 or 113 is multiplied.

Especially when the crossbar 18.5 is not about a pivot 18.8. can be pivoted (with corresponding devices for securing against rotation, such as a clamping screw, of course, being associated with the pin 18.8), the screw 27 may be difficult to access in certain cases at the location shown in FIG. 2, namely on a side face of the crossbar 18.5. The embodiment according to FIGS. 3 and 4 now differs from that according to FIG. 2 in that the screw 27 (FIG. 4) for each of the insertion openings 18.6 on the turret 13 or 113 (cf. FIGS. 1, 2 ) radially outermost surface 18.9 is accessible, so that it faces outwards in any position of the turret 13 or 113. This means that the wedge slide 25 then extends approximately in the radial direction of the revolver or in the longitudinal direction of the prismatic body 18.1.

3 also has a connection for a liquid line 29 of the turret 13 or a line system 30 housed in the interior of the clamping additive 18. This line system 30 lies, as can be seen, in a plane lying below the plane of the pin 18.2 and leads to outlets 30.1, 30.2 for connecting a coolant or lubricant line. Another outlet can be arranged in the interior of the insertion openings 18.6 in order to bring cooling and lubricating fluid into line systems 31 of the tool heads 21, 21 '. On the outside of the tensioning attachment 18, in particular on the outside surface 18.9, it is expedient for an actuation, which can also be seen particularly from FIG. 6 device 32 is provided for a shut-off or changeover valve in order to selectively supply the liquid from the line system 30 to one of the line systems 31 of the tool heads 21, 21 ', if desired also to both or none of them. It can be seen that the line systems 31 in the tool heads 21, 21 'push through the insertion pin 21.2 of these heads.

Since these insertion pins 21.2 are circular-cylindrical as shown, it is advantageous to provide the coupling surfaces 18.10 of the crossbeam 18.5 and / or the tool heads 21, 21 'with projections 21.3 or corresponding recesses 18.11 for securing against rotation. However, Oies is not necessarily the case; if the coupling surfaces 18.10 are designed or roughened in the manner of a friction clutch, this can be used to be able to set the maximum ore torque acting on the respective tool. In this case, it is advantageous if the wedge slides 25, which are used for establishing the connection and for applying a tensile force acting axially on the pins 21.2 against the coupling surfaces 18.10, are connected to a voltmeter (strain gauge, piezo crystal, etc.) in order to to be able to set the set coupling force and the maximum permissible torque which results from the insertion of the screw 27, as can be seen from the description of FIG. 5.

The reading device 22 'already mentioned above can also be seen from FIG. 3, which is directed against a side face of a merely indicated tool head 21 and the code 23 attached to it (cf. FIG. 4). As will be described with reference to FIG. 8, this reading device 22 'may be designed as a plug-in unit. Accordingly, an electrical plug coupling 33 may also be on the contact surface 18.3 of the tensioning attachment 18 be attached in order to feed the signals of the reading device 22 'to the turret 13 and from there to the numerical control 16 (FIG. 1).

Incidentally, it should be mentioned that it is not necessary to provide a projection 21.3 in the latter for the anti-rotation lock between the clamping attachment 18 and the tool head 21, rather the tool head 21 can also have a recess in which (in the visible manner) then a locking pin is inserted as a projection 21.3.

In Fig. 5 the details of the quick release fastener are shown enlarged. It can be seen that the screw 27 is only provided at its end with a threaded section 27.1 for screwing into the threaded bore 18.7 (cf. FIG. 2). Furthermore, it is shown that the clamping wedge 25.1 is only applied to the rear surface of the neck groove 21.1 in order to generate an axial tensile force on the insertion pin 21.2 and thus to place the tool head 21 or 21 'against the associated coupling surface 18.10 of the clamping attachment 18. This creates a very rigid connection, which in no way amplifies vibrations that occur during machining, on the contrary, they are rather damped by the different resonance frequencies due to the different sizes of the individual parts.

As will be explained in more detail with reference to FIG. 7, it is advantageous to guide the clamping wedge 25.1 only approximately over a quarter circle of the pin 21.2. A relatively small immersion depth in the neck groove 21.1 is then sufficient to tighten the pin 21.2. It is furthermore advantageous that there is surface contact between the clamping wedge 25.1 and the rear wall of the neck groove 21.1, so that these parts can absorb high clamping forces, which is rarely the case with proposals according to the prior art. It goes without saying that the construction with the compression spring 28 (and thus only a non-positive return of the wedge slide 25) could also be replaced by an inevitable adjustment, for example by securing the screw 27 on the wedge slide 25 against axial displacement. The type of seat of the spring 28 in the associated bore 18.12 of the tensioning attachment 18, indicated by dash-dot-dash lines, and its support against the end of this bore is clearly shown in FIG. 5.

The slightly different variant according to FIG. 5a also shows the wedge slide 25 with the clamping wedge 25.1 and the neck groove 21.1 on the insertion pin 21.8. The insertion pin 21.2 has an axial bore 76 for the cooling cutting fluid. The screw 27, which passes through the wedge slide 25 in a bore, has two counter nuts 70 which limit the axial freedom of movement of the Kei 1 slide 25 on the screw 27. To prevent the wedge slide from rotating, it has a longitudinal groove 71, into which a locking screw 72 engages in the assembled state. The locking screw 72 is screw-mounted in the crossbar 18. As a special feature, the wedge slide at its end facing away from the tensioning 25.1 has a push-off lug 73 which, with its push-off surface 74, contacts a phase 75 at the end of the insertion pin 21.2 as soon as the wedge slide 25 or the tensioning wedge 25.1 by means of screw 27 from the area of Neck groove 21.1 has given way to the release position. If the wedge slide 25 is pushed further in this direction, then the insertion pin 21.2 and thus the tool head are pressed out of the insertion opening 18.6 (FIG. 6).

This is important if, after long use, a strong compression or cohesive adhesion has arisen between the pin 21.2 and the opening 18.6. It is therefore always easy to remove the tool head. In itself, it would of course also be conceivable to also provide a VDI quick-release fastener on the clamping attachment 18, as for the insertion openings 17 of the revolver, the jaws: 19 (FIG. 2) also being designed in the manner of DE-OS 33 30 653 could or in any other known version. It should also be clear, however, that the quick-release fastener shown in FIG. 5, due to its tensioning force, acts in the direction of the pin 21. 2 V e rteltetet, so that this solution could possibly also be applicable to the openings 17 of the revolver.

The coupling effect, which can be achieved with such a tension lock, can be enhanced by appropriate design of the coupling surfaces in the manner of FIG. 6. In this case, the surfaces 18/10 can be recessed in a conical manner in the manner of a cone coupling (or can be n) or can be designed in the form of a dome. If it is desired to be able to turn the tool and head on the clamping attachment in any direction about the axis of the insertion opening 18.6, it may be appropriate to design the projections and depressions 18/11 as ribs. For example, these ribs 18/11 can run diagonally over the coupling surface 18/10, in which case, however, only rotation by 180 ° is possible. They are therefore preferably arranged radially to the axis of the insertion opening 18.6 in the manner shown in FIG. 6, which - depending on the spacing of the ribs - permits a significantly larger number of rotational positions.

If one considers the angled ends of the tools 4 in FIG. 1 in this context, it is understood that when the angular position of the tool head on a coupling surface 18/10 according to FIG. 6 changes, the relative position of the tool tip also changes. In such a case, it may be appropriate to provide a polygonal-prismatic instead of a cuboid-shaped tool head and to give it so many surfaces, as different rotational positions are conceivable. The associated code 23 for specifying the position of the cutting end of the tool can then be opposite a reading device 22 or 22 '(FIGS. 2, 3) on each surface.

6, the actuating member 32 for the valve provided in the interior of the crossbeam 18.5 can be seen more clearly, as a result of which the inflow of the cooling or lubricating liquid can be controlled. The valve can be of any known construction per se and - which may be of particular interest for the embodiment according to the invention - can also be actuated by the control 16 (FIG. 1), in which case it should be designed as a solenoid valve. If two workpieces on the two chucks 2, 2 'are to be machined one after the other or simultaneously, it may be desirable to also control the inflow of the liquid in the desired sequence from the numerical program. A simple design of the valve is shown in FIG. 10.

It has already been mentioned above that the design of the quick-release fastener according to FIG. 5 can be modified in various ways, although the design according to FIG. 5 is preferred. 7 shows the rear surface of the pin 21.2, in the neck groove of which two wedge slides 125, 225 engage with their wedge surfaces 25/1. The effect is essentially the same as described above with reference to FIG. 5, but the areas absorbing the pressure in the axial direction of the pin 21.2 thus increase. Theoretically, the wedge slides could also be enlarged as shown in dash-dotted lines with the wedge slider 125, so that a wedge area 25/1 of almost 180 ° results on each slide. In such a case, however, one-sided loads result for a single screw 127, so that its threaded part suffers as a result. Either such a screw would have to be tightened in the upper half shown in dash-dot lines bring, which does not exactly facilitate the handling, or the screws would have to attack from? white sides in the middle of the larger Ketlsch iver. In any case, two screws would then have to be actuated, so that the increase in the axial tensile force (by enlarging the surfaces 25/1 receiving them) would be at the expense of ease of use. This is another advantage of a wedge surface 25/1 or only covering a quarter circle. 25.1 can be seen: such an arrangement ensures a uniform force attack on the screw 27 or 127, with only a single screw being sufficient for actuation.

Otherwise, the design of this screw 127 would not be critical. Although it would be conceivable in itself to provide them with a left-hand and a right-hand thread in order to achieve a uniform movement of the wedge slides 125, 225 apart or against one another, it may be sufficient to provide only one end thread section 27.1 here, too, since centering at best can be done by moving the screw 27 in its axial direction. At most, a spring corresponding to the spring 28 (FIG. 5) may be provided between the two wedge slides 125, 225. However, where an axial displacement of the screw 127 is out of the question, two opposing threaded sections can also be provided for the two wedge slides 125, 225.

8 shows a reading device for the code 23 in a longitudinal section. To ensure a predetermined brightness, it will be advantageous to provide an illumination device in the form of a light source 34, optionally in the form of a GaAs laser diode. Their light is sent, expediently via a condenser 35, through a dividing prism 36, from where it enters along the optical axis 37 and via a deflecting mirror 38 Objective 39 crosses. The lens 39 is expediently designed as a wide-angle lens, and for two reasons: on the one hand, the distance to the surface of the tool head 21 bearing the code 23 will have to be limited for practical reasons, but the field of view of the lens has to be wide enough to accommodate the whole To capture code. On the other hand, wide-angle lenses are known to be less sensitive with regard to the depth of field, so that the image sharpness is retained even with certain tolerances.

The code 23 then reflects the light substantially perpendicular to the lens, enters the lens 39 and takes its path along the optical axis 37. At the dividing prism 36, part of the reflected steel is reflected and guided along an axis 37 '. This leads to an image analyzer 40, which can contain, for example, a row of light-sensitive diodes (so-called “diode array”). These diodes are then interrogated periodically via a shift register 41 ("scanning"), their respective charge value being fed to an evaluation circuit 42 for preparing the output signals of the reading device 22 '. From there, the signals pass through one of the plug contacts 33 'into the tensioning attachment 18 and via a corresponding line and the plug 33 (FIG. 3) to the controller 16 (FIG. 1).

It goes without saying that on the one hand the reading device 22 can be designed analogously, on the other hand there are also various other possibilities for coding and reading a code. For example, it has become known for other purposes from GB-OS 2 126 943 to provide an identification code for injection molds; a similarly designed code could each face the coupling surface 18.10 of the tensioning attachment, the pin-like projections 21.3 also could transmit electrical signals, at most a number of such plug pins is provided. Other codes have become known from photography for coding film sensitivity on film cassettes and could accordingly also be used here. In any case, the dimensional information required for the control 16 is automatically entered, not only saving time but also eliminating the possibility of errors.

In Fig. 1 two types of tools 3, 4 are indicated, of which the tool 4, as already mentioned, is a puncture knife. The slim tool. 3, on the other hand, may be designed as a drill or milling machine, in which case the tool generally rotates while the workpiece is stationary. In such a case, it may be desirable to provide a drive for the rotatable tool on the clamping attachment 18. FIG. 9 shows a variant for this, FIG. 10 shows another.

9 there is provided a shaft 43 which extends through the length of the body 18.1 and which carries a drive pinion 44 in a recess 45 at the end facing the VDI pin 18.2. As soon as the pin 18.2 is seated in the fastening opening 17 of the turret 13, the pinion 44 also comes into engagement with a drive gear 46 of the turret 13. The wheel 46 is and is in a recess 47 which starts from the end face 20 of the turret attached to a shaft 48 extending radially with respect to the turret 13. This shaft 48 can in turn be driven by a main shaft (not shown) passing through the hollow shaft 15 (FIG. 1) via a pair of bevel gears.

As can be seen, the outer circumference of the gear 46 protrudes somewhat beyond the end face 20 of the turret 13. This enables the shaft 43 to be mounted centrally within the body 18.1 (in plan view according to FIG. 9) without the pinion 44 therefore projecting beyond the boundary surfaces of this body 18.1. On the other hand, this arrangement means that clamping attachments which do not have a drive shaft 43 and nevertheless are to be connected to a turret 13 provided with gear wheels 46 must nevertheless have a recess 45 in order to accommodate the protruding part of the gear wheel 46.

Although it would be possible to also couple the coupling to the gear 46, 48 of the turret in another way, for example to use bevel gears instead of the gear 46, the spur gear shown is particularly suitable because of the necessary displacement of the shafts 43, 48.

In the area of the crossbeam 18.5, a bearing block 49 is preferably provided, in which the end of the shaft 43 and two further shafts 50, 51 are mounted. At this end, the shaft 43 carries a bevel gear 52 which meshes with corresponding bevel gears 53, 54 of the shafts 50, 51. At the other end, the shafts 50, 51 carry, within the insertion openings 18.6 couplings, for example claw couplings 55, which enter the correspondingly enlarged bores of the pins 21.2 (see FIG. 4) and there with a mating coupling (not shown) for the drive a short shaft 21.2 penetrating the pin for driving a turning tool (drill, milling machine or the like) can come into engagement. It has already been mentioned with reference to FIG. 3 that the lines 29, 30 are arranged in a plane below the plane of the pin 18.2. The pin-type projection 18.2 is therefore only indicated by dash-dotted lines in the sectional illustration in FIG. 10. For the connection of the two lines 29, 30, the line 29 expediently has a transverse bore 56 with an inserted fitting 57, to which the line 30 is connected. The line system 30 also has a longitudinal bore 58 which branches in the crossbar 18.5, the branch line 59 being closable via a valve 60.

The valve 60 can be actuated by the handle 32 already described, i.e. the handle (cf. FIG. 6) can be rotated with the aid of a screwdriver and thereby rotates a shaft 61 on which the valve body 60 is seated. The valve body 60 is of asymmetrical design, as can be seen, so that it closes a partial line 62 in one position and releases a partial line 63, but in another position, in turn, closes the latter and releases the former. In an intermediate position of the valve body 60, both lines 62, 63 are blocked, and it is conceivable to design the valve body 60 such that it releases both sub-lines in a fourth position.

The liquid is used for tool cooling. In this case, it is expedient to provide a central coolant outlet 65, which then connects to the power systems 31 (FIG. 4) of the pins 21.2.

A throttle valve will be arranged in each of the sub-lines 62, 63 for separately setting the flow rate of the cooling cutting means, but in most cases there will be a lack of space. Such a throttle valve 66 is indicated in the longitudinal line 58 in FIG. 10; it can be adjusted from the outside by means of a handle 67. Within the scope of the invention, numerous modifications are possible both of the features shown in combination with one another and in combination with features of the prior art. Although it can be seen that it is precisely through the combination of features according to the invention that a quick tool change and overall reduction of the total machining time is possible, it is understandable that some of the construction solutions shown also have independent inventive significance regardless of the arrangement and use of a clamping attachment 18 or 118 are. This applies above all to the design of the quick-release fastener described with reference to FIGS. 2, 5 and 7, but also to the coding of the tool heads and their use for automatically entering the dimensional information into the controller 16.

If desired, the line system 30 can also be used to actuate a wedge slide valve via a cylinder-piston unit. In this case, a pressure relief valve can be provided between such a unit and the sub-lines 62, 63 (FIG. 10), as a result of which the wedge slide first passes through the unit into the closed position and, when the line pressure in the system 30 is increased further, the liquid via the respective one , appropriately controllable (to shut off), pressure relief valve is supplied to the coolant outlet64.

In connection with FIG. 5 it will be understood that the wedge surface 25.1 must always be aligned with the neck groove 21.1. Because the wedge slide 25 is cylindrical or peg-like and the screw 27 is eccentric to its longitudinal axis, not only are the advantages explained with reference to FIG. 7 achieved, but also the correct position of the wedge surface 25.1 is automatically obtained while simultaneously preventing rotation. While only one single circumferential surface of the revolver 13 or 113 was mentioned in the above description, of course, several circumferential surfaces could also result if the revolver is chamfered. It would also be conceivable to equip the revolver with different fastening devices, in which case at least one of them as a quick-release fastener with the jaws 19 or the like. to hold the ribbed fastening surface on the projection 18.2.

Further modifications can consist in the fact that only one of the shafts 50 or 51 is provided, in particular if the crossbar 18.5 is designed as a revolver. The chuck 2 'could also be designed without a drive for drilling and milling work. It also goes without saying that instead of insertion holes 18.6, push-on pins may also be provided as the fastening device.

It also goes without saying that it is preferred to design the cutters 1, 17, 19 and 25, 27 shown and discussed as standard connections, so that they are compatible with conventional connections. In the case of the machine tool being designed for machining with a reciprocating movement, in the case of the embodiments according to FIGS. 9 and 10, the rotary drive could be operated via a, e.g. Already in the clamping attachment, preferably in the tool head to be connected to it, the eccentric to be provided can be converted into a reciprocating movement. However, this is not the only possibility, since the variant would be conceivable to provide a hydraulic vibrator instead of such an eccentric, especially in the embodiment according to FIG. 10 (with a liquid line).

Claims

PATENT CLAIMS

1. Machine tool, for example a lathe, for machining workpieces which can be clamped to a geometric machining axis by means of a chuck, with a turret head having at least one end face and a circumferential surface with a plurality of turrets over the turret head along a circle lying in a normal plane to the machining axis Distributed fastening devices for alternately inserting tools, characterized in that at least one of the following features is provided: a) a special clamping attachment (18) is assigned to each fastening device (17, 19) of the turret head (13; 113) and by means of the fastening device (17, 19) can be fastened to the turret (13; 113), with each clamping attachment (18) having at least one further fastening device (25, 27) which is designed as a quick-release fastener, the geometric dimensions of which are related to the machining axis (5, 5 ') a precisely defined position can be placed, to which clamping attachments (18) at least one tool holder (21) with a connection piece (21.1) for the quick release (25, 27) can be connected; b) at least one clamping attachment (18) can be connected to each fastening device (17), which has a machine-side tool drive (29; 46, 48) via a coupling (44, 45; 57) provided thereon with a drive connection (52; 59) for driving the respective tool, and which has at least one connection (18.6) for connecting a tool attachment surface (21.1, 21.2); c) depending on the fastening device (17, 19) because a clamping attachment (18) can be fastened, which extends radially beyond the circumferential surface (14) of the turret (13; 113) and has the fastening surface (18.2) for the fastening device (17, 19) at one end and along the radially outer end has an axis running parallel to the turret axis (15) on opposite and facing surfaces (18.10) each has a fastener (25, 27) for a tool holding head (21 or 21 ') designed as a quick-release fastener; d) a reading device (22, 22 ') for a code (23) indicating the respective tool dimensions for the positioning of the tool (3, 4) is connected to a numerically controlled drive (16) for the relative movement of the tool and the workpiece.

2. Clamping attachment for a machine tool according to claim 1, characterized in that it has an elongated, at least approximately prismatic body (18.1) with a contact surface (18.3) for the end face (20) of the turret (13; 113), at one end a pin-like projection (18.2) with the fastening surface for insertion into a receiving opening (17) of the turret head (13; 113) protrudes perpendicularly from the contact surface (18.3), whereas at the other end on mutually opposite and mutually facing surfaces (18.10), of which one is arranged parallel or in alignment with the contact surface (18.3), receiving devices (18.6, 18.10) for a tool head (21, 21 ') are arranged, each of which is assigned a quick-release fastener (25, 27; 21.1).

3. Clamping attachment according to claim 2, characterized in that at least one of the following features is provided: a) at least one of the mutually opposite and mutually facing surfaces (18.10) forms the end face of a crossbar (18.5) arranged perpendicular to the elongated body (18.1); b) the end carrying the receiving devices, preferably in the form of insertion holes (18.6), can itself be turned in a revolver-like manner about an axis (18.8) lying parallel or in alignment with the longitudinal axis of the elongated body (18.1).

4. Clamping attachment according to claim 2 or 3, characterized in that at least one of the following features is provided: a) the drive device (43, 44; 30, 58) provided between the coupling (44, 45; 57) and the drive connection (52; 59) , 66) is housed inside the clamping attachment; b) the coupling (44, 46; 57) is located in the region of the pin-like projection (18.2); c) in the area of the drive connection (52), a corner gear (52-54) is provided for driving a transverse shaft (50 or 51), in particular via bevel gears (52-54).

5. Clamping attachment according to one of claims 2 to 4, characterized in that at least one of the opposing and facing surfaces (18.10) as a coupling surface (18.10; 18/10), e.g. is designed in the manner of a friction or claw clutch to secure the rotational position of the tool head (21, 21 '),

and that preferably at least one of the following features is provided: a) the coupling surface (18/10) has projections and / or recesses (18.11; 18/11) for receiving corresponding recesses and / or projections (21.3) of the tool head (21, 21 '), which in particular as over the coupling surface (18/10) extending ribs (18/11) are formed and expediently as radial jets to an insertion hole (18.

6) are arranged; b) the coupling surface (18/10) is shaped differently from a flat surface, for example conical or spherical.

Clamping attachment according to one of claims 2 to 5, characterized in that it has at least one liquid line (30), optionally one for liquid supply and discharge, which at its end has a line coupling (56, 57) in the region of the pin-like projection (18.2) for a turret-side connection (29, 56) and extends to the area of the other end,

and that preferably at least one of the following features is provided: a) the line (30) is provided for lubricants;

b) at least one drive unit for actuating a quick-release fastener is provided on the line (30); c) the line (30) contains at least one control valve (60 or 66), through which the liquid supply can be throttled and / or blocked at least to a partial area (58) of the line (30), the valve (60) optionally as a changeover valve , for example to release the hydraulic drive, in particular after the tool has been quickly clamped.

7. Clamping attachment according to one of claims 2 to 6, characterized in that the quick-release fastener (25, 27) has a wedge surface (25.1) which can be displaced transversely to the respective receiving device (18.6) with the aid of an actuating device (27), through which the tool head (21, 21 ') can be axially clamped to the respective surface (18.10) of the clamping attachment (18),

and that preferably at least one of the following features is provided: a) the actuating device has a screw (27) with at least one threaded section (27.1), optionally two threaded sections of opposite pitch, which is expediently eccentric in a, in particular cylindrical, sliding pin (25) is arranged to its longitudinal axis and / or has the threaded section (27.1) at its end for screwing into an internal thread (18.7) of the tensioning attachment (18), the displacement of the wedge surface (25.1) in the opposite direction preferably being non-positively with the aid of an internal thread (18.7 ) and wedge surface (25.1) provided spring (28); b) the wedge surface (25.1) is provided on a flange which can be pushed into a neck (21.1) of a tool head part 1 and forms at least approximately a quarter circle and a maximum of a semicircle; c) the wedge surface (25.1) can be displaced in the longitudinal direction of the elongated body (18.1), the actuating device (27, 28) preferably on the surface (averted from the peg-like projection (18.2) and lying essentially parallel to the longitudinal extension of the projection (18.2) 18.9) ends and is accessible from there.

8. Clamping attachment according to one of claims 2 to 7, characterized in that the cross section of the wedge surface (25.1) having the component (25) and its Receiving opening is angular, and / or at the end of the wedge surface a cam is provided, which is brought into contact with a fastening surface of the tool head (21, 21 ') and driven by the actuating device, which presses it out of the quick-release fastener.

9. Tool head for a machine tool according to claim

1 or for a clamping additive according to one of the claims

2 to 8, with an insertion section for insertion into a receiving opening, characterized in that the insertion section (21.2) is provided with a neck groove (21.1) and / or that the tool head (21, 21 ') on one of its outer surfaces defines the tool dimensions for the positioning of the machining end indicating machine-readable code (23).

10. Clamping attachment according to one of the preceding claims, characterized in that it can be removed for each connection device from a series of slightly different clamping attachments, or that for each clamping attachment, intermediate layers for varying the contact surface for adjusting the defined location of the geometric dimensions, the or the quick fastener or quick fasteners are provided.